BIOD 152 Module 6 Exam Digestive Metabolism Urinary Fluid
Balance Actual Exam 2026/2027 – Complete Questions with
Detailed Rationales | 100% Verified | Pass Guaranteed – A+
Graded
SECTION A: Digestive System Anatomy & Histology (Q1–Q6)
Q1: In a histology slide of the small intestine, the wall of the alimentary canal shows
four distinct tunics. From the lumen outward, which is the correct order of these layers?
A. Serosa, muscularis externa, submucosa, mucosa
B. Mucosa, muscularis externa, submucosa, serosa
C. Mucosa, submucosa, muscularis externa, serosa [CORRECT]
D. Submucosa, mucosa, serosa, muscularis externa
Correct Answer: C
Rationale: From the lumen outward, the four tunics of the GI tract are the mucosa,
submucosa, muscularis externa, and serosa (or adventitia). The distractors reverse or
scramble this standard arrangement.
Q2: A 45-year-old man reports burning pain behind the sternum that worsens when lying
down after large meals, and he is diagnosed with GERD. Failure of which structure is
responsible for the reflux of gastric contents into the esophagus?
A. The pyloric sphincter
B. The lower esophageal sphincter [CORRECT]
C. The upper esophageal sphincter
D. The ileocecal sphincter
Correct Answer: B
Rationale: The lower esophageal (cardiac) sphincter normally prevents acidic gastric
contents from refluxing into the esophagus; its incompetence produces heartburn. The
pyloric and ileocecal sphincters regulate gastric emptying and colonic backflow, and the
upper sphincter governs swallowing.
Q3: Which cells of the gastric glands secrete hydrochloric acid and intrinsic factor?
A. Chief cells
B. Mucous neck cells
C. G cells
, D. Parietal cells [CORRECT]
Correct Answer: D
Rationale: Parietal cells secrete HCl (activating pepsinogen) and intrinsic factor,
required for vitamin B12 absorption. Chief cells secrete pepsinogen, mucous cells
protect the mucosal lining, and G cells release gastrin.
Q4: A patient who has had a cholecystectomy is told that fat digestion will continue
because bile still drips into the duodenum directly from its site of production. What was
the gallbladder's role?
A. Storing and concentrating bile produced by the liver [CORRECT]
B. Producing bile and digestive enzymes
C. Secreting cholecystokinin to digest fats
D. Emulsifying fats with bile enzymes
Correct Answer: A
Rationale: The gallbladder stores and concentrates bile produced by the liver, releasing
it in response to CCK; bile itself contains no enzymes, so options claiming enzyme
production or emulsification by enzymes are incorrect.
Q5: A patient on prolonged broad-spectrum antibiotics develops diarrhea and a
tendency to bruise easily due to impaired vitamin K synthesis. Normal bacterial flora
that produce vitamin K are located primarily in which organ?
A. The stomach
B. The duodenum
C. The large intestine [CORRECT]
D. The liver
Correct Answer: C
Rationale: Beneficial bacteria of the large intestine synthesize vitamin K and several B
vitamins; destroying this flora with antibiotics can impair clotting. The stomach,
duodenum, and liver do not host vitamin K–producing flora.
Q6: During digestion in the small intestine, which mechanical process is the primary
movement that churns and mixes chyme with bile and pancreatic juice, rather than
propelling it forward along the tract?
A. Peristalsis
B. Mastication
C. Haustral churning
D. Segmentation [CORRECT]
Correct Answer: D
Rationale: Segmentation is the alternating contraction and relaxation of circular muscle
that mixes chyme with secretions in the small intestine. Peristalsis propels contents
Balance Actual Exam 2026/2027 – Complete Questions with
Detailed Rationales | 100% Verified | Pass Guaranteed – A+
Graded
SECTION A: Digestive System Anatomy & Histology (Q1–Q6)
Q1: In a histology slide of the small intestine, the wall of the alimentary canal shows
four distinct tunics. From the lumen outward, which is the correct order of these layers?
A. Serosa, muscularis externa, submucosa, mucosa
B. Mucosa, muscularis externa, submucosa, serosa
C. Mucosa, submucosa, muscularis externa, serosa [CORRECT]
D. Submucosa, mucosa, serosa, muscularis externa
Correct Answer: C
Rationale: From the lumen outward, the four tunics of the GI tract are the mucosa,
submucosa, muscularis externa, and serosa (or adventitia). The distractors reverse or
scramble this standard arrangement.
Q2: A 45-year-old man reports burning pain behind the sternum that worsens when lying
down after large meals, and he is diagnosed with GERD. Failure of which structure is
responsible for the reflux of gastric contents into the esophagus?
A. The pyloric sphincter
B. The lower esophageal sphincter [CORRECT]
C. The upper esophageal sphincter
D. The ileocecal sphincter
Correct Answer: B
Rationale: The lower esophageal (cardiac) sphincter normally prevents acidic gastric
contents from refluxing into the esophagus; its incompetence produces heartburn. The
pyloric and ileocecal sphincters regulate gastric emptying and colonic backflow, and the
upper sphincter governs swallowing.
Q3: Which cells of the gastric glands secrete hydrochloric acid and intrinsic factor?
A. Chief cells
B. Mucous neck cells
C. G cells
, D. Parietal cells [CORRECT]
Correct Answer: D
Rationale: Parietal cells secrete HCl (activating pepsinogen) and intrinsic factor,
required for vitamin B12 absorption. Chief cells secrete pepsinogen, mucous cells
protect the mucosal lining, and G cells release gastrin.
Q4: A patient who has had a cholecystectomy is told that fat digestion will continue
because bile still drips into the duodenum directly from its site of production. What was
the gallbladder's role?
A. Storing and concentrating bile produced by the liver [CORRECT]
B. Producing bile and digestive enzymes
C. Secreting cholecystokinin to digest fats
D. Emulsifying fats with bile enzymes
Correct Answer: A
Rationale: The gallbladder stores and concentrates bile produced by the liver, releasing
it in response to CCK; bile itself contains no enzymes, so options claiming enzyme
production or emulsification by enzymes are incorrect.
Q5: A patient on prolonged broad-spectrum antibiotics develops diarrhea and a
tendency to bruise easily due to impaired vitamin K synthesis. Normal bacterial flora
that produce vitamin K are located primarily in which organ?
A. The stomach
B. The duodenum
C. The large intestine [CORRECT]
D. The liver
Correct Answer: C
Rationale: Beneficial bacteria of the large intestine synthesize vitamin K and several B
vitamins; destroying this flora with antibiotics can impair clotting. The stomach,
duodenum, and liver do not host vitamin K–producing flora.
Q6: During digestion in the small intestine, which mechanical process is the primary
movement that churns and mixes chyme with bile and pancreatic juice, rather than
propelling it forward along the tract?
A. Peristalsis
B. Mastication
C. Haustral churning
D. Segmentation [CORRECT]
Correct Answer: D
Rationale: Segmentation is the alternating contraction and relaxation of circular muscle
that mixes chyme with secretions in the small intestine. Peristalsis propels contents
